Io BOTANICAL GAZETTE [JULY 
It is probable that a careful study of the sprouting seed will 
show the meaning of some of these peculiarities to the plant. 
I hope soon to be able to determine whether the tissue which I 
have called endosperm here has the same function as in Sauru- 
rus, of absorbing the perisperm for the benefit of the embryo 
during the sprouting of the seed. I trust also that a further 
study of related forms may discover some intermediate type of 
embryo-sac, that will indicate more definitely the possible deriva- 
tion of the peculiar one found in Peperomia. 
In conclusion and summary: the macrospore nucleus of; 
Peperomia pellucida forms sixteen free nuclei, of which one goes 
to the egg, one to the synergid, eight more fuse to form a single 
endosperm nucleus, while the other five remain sterile and 
degenerate. The nearly ripe seed contains an embryo of fifteen 
or more cells surrounded by endosperm cells in which the walls 
are formed directly from the cell plate of the spindle. 
JoHNs Hopkins UNIVERSITY, 
Baltimore. 
LIST OF WRITINGS REFERRED TO. 
CAMPBELL, D. H.: Die Entwickelung des Embryosackes von Peperomia pel- 
ucida Kunth. Berichte d. Deutschen botanischen Gesells. 17 : 452 . 1899: 
HOFMEISTER, W.: Neue Beitriige z. Kentniss d. Embryobildung d, Phanero- 
gamen. Abhandl. d. K. sachs. Gesellsch. d. Wissensch. 6: —. 1859- 
Lotsy, J. P.: Contributions to the life history of the genus Gnetum. Annales 
du Jard. Bot. de Buitenzorg II. 1: 46. 1899. 
MANN, G.: Development of the macrosporangium of J/yosurus minimus. 
Trans. Bot. Soc. Edinburgh. 1892. 
SCHMITz, F.: Die Bliithenentwicklung der Piperaceen. Hanstein Bot. 
Abhandl. 2: 1875. 
STRASBURGER, E.: 
Die Angiospermen und Die Gymnospermen. Jena. 1879- 
: Zellbildung und Zelltheilung, Dritte Auflage. Jena. 1880. 
EXPLANATION OF PLATE I. 
Abbreviations used: ax, axis of the inflorescence ; 47, subtending bract; 
cp, carpel; em, embryo; es, embryo-sac ; esf, endosperm; esfz, endosperm 
nucleus; ¢sv, principal vacuole of embryo-sac ; esw, wall of embryo-sac ; 74, 
integument; mf, micropyle; zc, nucellus ; 9, oosphere nucleus ; osf, oospore ; 
